A number of factors contribute to the establishment and maintenance of many chronic autoimmune and inflammation disorders. Often, the etiology of such disorders is not well understood. Tumor necrosis factor-α (TNFα) is a cytokine that is released primarily by mononuclear phagocytes in response to a number immunostimulators. When administered to animals or humans, it causes inflammation, fever, cardiovascular effects, hemorrhage, coagulation, and acute phase responses similar to those seen during acute infections and shock states. Excessive or unregulated TNFα production is thus implicated in a number of disease conditions. These include endotoxemia and/or toxic shock syndrome, e.g., Tracey et al., Nature 330:662-664 (1987) and Hinshaw et al., Circ. Shock 30:279-292 (1990), cachexia, e.g., Dezube et al., Lancet, 335 (8690):662 (1990) and ARDS where high TNFα concentrations have been detected in pulmonary aspirates from ARDS patients, e.g., Millar et al., Lancet 2(8665):712-714 (1989).
TNFα also may be involved in bone resorption diseases, including arthritis. When activated, leukocytes can produce bone-resorption, an activity to which TNFα may contribute, e.g., Bertolini et al., Nature 319:516-518 (1986) and Johnson et al., Endocrinology 124(3):1424-1427 (1989). TNFα also has been shown to stimulate bone resorption and inhibit bone formation in vitro and in vivo through stimulation of osteoclast formation and activation combined with inhibition of osteoblast function. Blocking TNFα with monoclonal anti-TNFα antibodies has been shown to be beneficial in rheumatoid arthritis (Elliot et al., Int. J. Pharmac. 17(2):141-145 1995) and Crohn's disease (von Dullemen et al., Gastroenterology, 109(1):129-135 2005).
The nuclear factor-kappaB (NF-κB) molecule is a mediator of inflammation in a number of clinical conditions. Some therapeutic agents that are used to treat inflammation such as dexamethasone, prednisone or hydrocortisol are glucocorticoid receptor (GR) agonists and they indirectly inhibit NF-κB by increasing the activity of the GR, e.g., H. Harkonarson et al., Am. J. Respir. Cell Mol. Biol. 25:761-771, 2001. However, elevated levels of natural GR agonists and pharmacological levels of synthetic GR agonists usually exert unwanted toxicities including significant immune suppression and loss of bone mass or osteopenia, e.g., T. L. Popper et al., Anti-inflammatory agents: Anti-inflammatory steroids, R A. Scherer & M. W. Whitehouse, editors, Academic Press, New York, Chapter 9, volume 1, pages 245-294, 1974. Many of the unwanted toxicities associated with glucocorticoids are caused by activation of the GR. Thus, Identification of compounds that can inhibit NF-κB activity without causing these toxicities by activating the GR represents a class of agents that could be used to treat inflammation and associated symptoms such as pain, fever or fatigue.
Unwanted or damaging inflammation occurs in a number of chronic or acute conditions, e.g., ARDS, COPD and sepsis. Activated monocytes and neutrophils may play a role in mediating inflammation associated pathology in some of these conditions. Activated neutrophils can have increased NFκ-B in the nucleus and increased production of proinflammatory cytokines. Neutrophils can be a source of toxic oxygen species whose generation mediates, at least in part, tumor necrosis factor-alpha (TNF-α) secretion by activated macrophages. TNFα may be necessary for some of the organ injury and failure that can be seen in sepsis.
Signaling associated with inflammation can occur through different pathways and this can increase the activity of NF-κB in affected cells. NF-κB activation by tumor necrosis factor-α (TNF-α) starts with binding of TNF-α to the TNF-α receptor at the cell membrane, followed by activation of a series on signal transducers including MAP kinases. Activation of NF-κB in the cytoplasm leads to its translocation into the nucleus and activation of genes that contain the NF-κB response element in their promoters. Activation of cytoplasmic NF-κB by bacterial lipopolysaccharide (LPS) begins with binding of LPS to Toll-like receptor 4 at the cell surface and subsequent activation of intracellular signal transducers, including phosphatidylinositol-3-kinase. TNF-α and LPS are both known to induce intense inflammatory responses in vivo and in cells in vitro. Cells that respond to such proinflammatory signals include macrophages, monocytes and other types of immune cells.
Various T cell subsets appear to have a role in the development of certain disease conditions. An important role for a distinct T cell populations including regulatory and/or suppressor T cells in mediating various aspects of immunity has been suggested, e.g., E. Suri-Payer et al., J. Immunol., 160(3): 1212-1218, 1998; J. Shimizu et al., J. Immunol., 163(10):5211-5218, 1999; M. Itoh et al., J. Immunol., 162(9):5317-5326, 1999; A. M. Miller et al., J. Immunol., 177:7398-7405, 2006. CD4+ CD25+ T cells may play a role in suppressing some immune responses.
Study of some of these T cell subsets in animal models have been described, e.g., U.S. Pat. No. 6,593,511. For example, a role for the study of human autoimmune conditions was examined in the scid/scid CD4+ CD45Rbhi model. This animal model has been used to study dysregulated immune responses such as inflammation conditions and to evaluate experimental drugs and treatment protocols, e.g., K. Hong et al., J. Immunol., 162:7480-7491, 1999; Powrie et al., J. Exp. Med., 183(6):2669-2674, 1996.
The Foxpro3 gene, which is induced by thymus epithelium may play a role in inducing T cells to develop the CD4+CD25+ or CD4+CD25high (Treg or regulator T cell) phenotype. The CD25 surface antigen is the IL-2 receptor α-chain. In some animal models of autoimmune diseases, deficiency of the Foxpro3 gene is associated with the occurrence of autoimmune diseases, e.g., U.S. patent application No. 2006/0111316. Restoration of this gene appears to reduce autoimmune anomalies. Various reagents or assay protocols for CD4+CD25+ cells have been described, e.g., H. Yagi et al., International Immunol., 16(11):1643-1656, 2004; W. R. Godfrey et al., Blood, 105 (2)750-758, 2005.
Insulin resistance in glucose intolerant subjects has long been recognized. Reaven et al (American Journal of Medicine, 60(1):80-88, 1976) used a continuous infusion of glucose and insulin (insulin/glucose clamp technique) and oral glucose tolerance tests to demonstrate that insulin resistance existed in a diverse group of nonobese, nonketotic subjects. These subjects ranged from borderline glucose tolerant to overt, fasting hyperglycemia. The diabetic groups in these studies included both insulin dependent (IDDM) and noninsulin dependent (NIDDM) subjects.
Coincident with sustained insulin resistance is the more easily determined hyperinsulinemia, which can be measured by accurate determination of circulating plasma insulin concentration in the plasma of subjects. Hyperinsulinemia can be present as a result of insulin resistance, such as is in obese and/or diabetic (NIDDM) subjects and/or glucose intolerant subjects, or in IDDM subjects, as a consequence of over injection of insulin compared with normal physiological release of the hormone by the endocrine pancreas.
The association of hyperinsulinemia with obesity and with ischemic diseases of the large blood vessels (e.g. atherosclerosis) has been described by experimental, clinical and epidemiological studies (Stout, Metabolism, 34:7, 1985; Pyorala et al, Diabetes/Metabolism Reviews, 3:463, 1987). Statistically significant plasma insulin elevations at 1 and 2 hours after oral glucose load correlate with an increased risk of coronary heart disease.
One model of human diabetes is the db/db mouse. The db/db mouse model has been described, e.g., D. Koya et al., The FASEB Journal, 14:439-447, 2000; K. Kobayashi et al., Metabolism, 49(1): 22-31, 2000; J. Berger et al., J. Biol. Chem., 274(10):6718-6725,1999. The db/db mice carry a mutation in the gene encoding the leptin receptor, which confers a phenotype characterized by hyperphagia, obesity, insulin resistance and diabetes as their functional pancreatic β-cell mass deteriorates over time, particularly for animals in the C57BL/Ks genetic background. The db/db mice typically become identifiably obese at around 3 to 4 weeks of age and elevations of plasma insulin begin at 10 to 14 days. Elevations of blood sugar are seen at 4 to 8 weeks of age with an uncontrolled rise in blood sugar, severe depletion of the insulin producing β-cells of the pancreatic islets, and death by about 10 months of age. This model has been used to characterize the capacity of drug candidates to affect the onset or rate of progression of parameters, e.g., hyperglycemia and weight gain, related to the development and maintenance of diabetes.
Treatment of diabetes with PPAR-γ agonists has been associated with cardiac hypertrophy, or an increase in heart weight. Treatment with rosiglitazone maleate, a PPAR-γ agonist, indicate that patients may experience fluid accumulation and volume-related events such as edema and congestive heart failure. Cardiac hypertrophy related to PPAR-γ agonist treatment is typically treated by discontinuing the treatment.
A physiological effect of cortisol is its antagonism to insulin. High cortisol concentrations in the liver can reduce insulin sensitivity in that organ, which tends to increase gluconeogenesis and increase blood sugar levels (M. F. Dallman et al. Front Neuroendocrinol., 14:303-347, 1993). This effect aggravates impaired glucose tolerance or diabetes mellitus. In Cushing's syndrome, which is caused by excessive circulating concentrations of cortisol, the antagonism of insulin can provoke diabetes mellitus in susceptible individuals (E. J. Ross et al., Lancet, 2:646-649, 1982).
Cortisol can be converted in the body to cortisone by the 11b-dehydrogenase activity of 11b-hydroxysteroid dehydrogenase enzymes. The reverse reaction, converting inactive cortisone to active cortisol, is accomplished in certain organs by the 11b-reductase activity of these enzymes. This activity is also known as corticosteroid 11b-reductase activity. There are at least two distinct isozymes of 11β-hydroxysteroid dehydrogenase. Expression of 11β-HSD type 1 in a range of cell lines generates either a bi-directional enzyme or a predominant 11β-reductase, which can regenerate 11β-hydroxysteroid from the otherwise inert 11-keto steroid parent.
Mitochondrial phosphoenolpyruvate carboxykinase (also known as PEPCK-mitochondrial, PEPCK-M, PCK2 and mtPEPCK) is expressed in a variety of human tissues, mainly the liver, kidney, pancreas, intestine and fibroblasts (Modaressi et al., Biochem. J., 333:359-366, 1998). PEPCK-mitochondrial deficiency, while not well documented, has been associated with failure to thrive, hypoglycemia and liver abnormalities. Unlike the cytosolic form (PEPCK-C), the mitochondrial form (PEPCK-mitochondrial) is expressed constitutively and is not regulated by hormonal stimuli (Hanson and Patel, Adv. Enzymol. Relat. Areas Mol. Biol., 69:203-281, 1994). The two forms are located on separate chromosomes with localized to chromosome 14q11 and PEPCK-C resides on chromosome 20q11 (Stoffel et al., Hum. Mol. Genet. 2:1-4, 1993).
Multiple sclerosis (MS) is an autoimmune disease that is an inflammatory disease of the central nervous system (Bar-Or, A., J. Neuroimmunol. 100:252-259, 1999). Although the natural course of the disease has recently been improved by treatment with immunomodulatory-immunosuppressive compounds such as Interferon (IFN)-beta, copolymer, cyclophosphamide and mitoxantrone (Hafler, D. A. and Weiner, H. L., Immunological Reviews 144:75, 1995; Goodkin, D. E., Lancet 352: 1486, 1998), none of these drugs can block progression of disease and some of them have serious side-effects that limit their prolonged use. In addition, a substantial number of patients with both relapsing-remitting and secondary progressive MS exhibit poor response to IFN-β. Therefore, there is a need for novel compounds that alone or in combination therapy improve the course of MS by e.g., slowing its progression.
There is a current need for cost-effective pharmaceutical agents or treatment methods that are more effective in treating conditions described herein. The present invention provides therapeutic agents and treatment methods to treat one or more of the conditions described herein. The claimed agents and methods are useful to reduce one or more symptoms associated with the conditions described herein. Also, the use of the invention agents and methods can be combined with one or more conventional treatments for these disorders.